Animal morphogenesis as phase transition Dynamics

by Prof. Erez Braun

Faculty of Physics, Technion - Israel Institute of Technology

at Biological and soft-matter physics

Thu, 15 Feb 2024, 12:10
Sacta-Rashi Building for Physics (54), room 207; and ZOOM hybrid, link attached.

Abstract

A remarkable hallmark of animal morphogenesis is the robust convergence of this process into a stereotypic body form of a viable organism. Hydra regeneration provides a unique experimental setup, allowing us to develop a physics framework for this pattern-formation process. We demonstrate that by tuning an external electric field, we can drive morphogenesis in whole-body Hydra regeneration, back and forth, around a critical point in a controlled manner. Our control of morphogenesis allows us to characterize the primary morphological transition — from a nearly spherical structure to an elongated cylindrical shape, the final body form of a mature Hydra. We found that spatial fluctuations of the calcium distribution in the Hydra’s tissue drive this transition and constructed a field-theoretic model that explains the morphological transition as a first-order–like phase transition. The theory predicts and the experiments show the prominent role of fluctuations in Hydra morphogenesis. A periodically modulated electric field leads to a new induced phase of the regenerating tissue, showing stochastic morphological swings, back and forth, between a nearly spherical structure and an elongated cylindrical shape with dynamics characteristic of a stochastic resonance; the tissue’s response to the perturbation exhibits a resonance-like behavior as a function of the noise level.

For ZOOM hybrid:

https://us02web.zoom.us/j/85306683738?pwd=eldEbUZQTFl6V25DbFhWT25mdVR0dz09

Meeting ID: 853 0668 3738
Passcode: 345123

Created on 08-01-2024 by Granek, Rony (rgranek)
Updaded on 14-02-2024 by Granek, Rony (rgranek)